
Constructing Load-balanced Data Aggregation Trees
155
give the formal definition of the parent node assignment for leaf nodes to non-leaf
nodes as follows:
Definition 7.6 Parent node assignment for leaf nodes (A
L
). For a probabilistic
WSN represented by graph G(V,E,P(E)) and a CMIS D = {v
1
,v
2
,···,v
m
}, we need
to find m disjoint sets on V, denoted by L(v
1
),L(v
2
),···,L(v
m
), such that:
1. Each set L(v
i
)(1 ≤i ≤m) contains exactly one non-leaf node v
i
.
2.
m
i=1
L(v
i
)=V,andL(v
i
)
L(v
j
)=∅ (1 ≤i = j ≤ m).
3. ∀v
u
∈ L(v
i
)(1 ≤i ≤m) and v
u
= v
i
, such that (v
u
,v
i
) ∈ E.
4. Assign v
i
(1 ≤i ≤ m) as the parent node of the nodes in L(v
i
)\{v
i
}.Aparent
node assignment for leaf ...